[Elecraft] K2 RF Output

[Don Wilhelm]

That won't work - the KPA100 must be physically removed to keep the base 
K2 from using the KPA100 wattmeter.

73,
Don W3FPR

On 8/8/2021 1:54 PM, Frank Krozel wrote:
> Just power the radio, not the PA
> -73-  Frank    KG9H
> kg9hfrank at gmail.com <mailto:kg9hfrank at gmail.com>
>
>
>
>
>> On Aug 8, 2021, at 12:16 PM, jerry <jerry at tr2.com 
>> <mailto:jerry at tr2.com>> wrote:
>>
>> All,
>>
>>   Can I just remove the KPA100 and test the K2 "bare" for current draw?
>>
>>                 - Jerry KF6VB
>>
>>
>> On 2021-08-08 09:49, Don Wilhelm wrote:
>>> Jerry,
>>> Replace diodes D16 and D17 in the KPA100 wattmeter, and things should
>>> settle down.
>>> If you attempted to adjust KPA100 C1 while this condition was present,
>>> balance the wattmeter again, it will change with good diodes
>>> installed.
>>> The diodes are 1N5711 type.
>>> That wattmeter is still used as long as the KPA100 is installed on the
>>> base K2 - reducing the power to less than 12 watts does not take it
>>> out of line.
>>> CAL CUR should be set at 3.5 amperes with the KPA100 installed. That
>>> (and the current display) is the current drawn by only the base K2,
>>> and not to the KPA100.
>>> 73,
>>> Don W3FPR
>>> On 8/8/2021 12:24 PM, jerry wrote:
>>>> All,
>>>>   My new QRO K2 behaves a little strangely...
>>>> On Tune - it makes 108W on 40M, very nice.
>>>> But on 20M it behaves strangely.  It won't make more than 20W or 
>>>> so, complains about high SWR. Even though my Heathkit HM-102 
>>>> SWR/Wattmeter says the SWR is zilch.
>>>> So I moved it to a dummy load.  As I turn the power up, it makes up 
>>>> to about 80W, and then says "Hi CURR".  And it claims that the 
>>>> dummy load ( an 800W "Florida RF" resistor bolted to a large 
>>>> heatsink ) is 1.6 to 1, which is totally bogus.
>>>> OK, there's a null trimmer for the SWR bridge.  I got it down to 
>>>> 1-to-1 SWR on 20M.  It degrades on higher bands though - up to 1.5 
>>>> to 1 on 10M.
>>>> Now, 20M gives me a max of 45W - above that it complains "HI CUR".  
>>>> It's doing that on all bands. With the PA off via menu, I get a 
>>>> maximum of about 8.5W before getting the "HI CUR" message. I tried 
>>>> setting the current up a little bit on the CAL CUR menu, but no 
>>>> real difference.
>>>>   With a clamp-on DC ammeter ( which I don't trust THAT much ) I 
>>>> see 340mA on receive,
>>>> and just about 3.6A when the display goes "HI CUR". This is with 
>>>> the PA turned off.  The
>>>> display shows 7W just before this happens.  Hmm, 13.8V times 3.5A 
>>>> means 48.3W DC input.  Seems a little excessive.
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